1. Field of the Invention
This invention relates to a battery condition monitor and monitoring method by which the remaining capacity and service life of an storage battery, e.g. an automotive vehicle storage battery, can be monitored.
2. Description of the Prior Art
The primary function of an automotive vehicle storage battery is to supply current to a starter motor and an ignition system when an engine is being started. It also supplies current for lights, radio, and other electrical accessories when an alternator is not handling the electrical demand. A battery condition monitor serves to back the storage battery up and perform its essential function when the remaining capacity and service life of the storage battery drop below acceptable levels.
Japanese published unexamined patent application No. 53-127646 discloses a prior art battery condition monitor which measures the remaining capacity of the storage battery by means of the supported rate between the internal impedance and the remaining capacity of the storage battery.
However, since this rate depends on the remaining service life of the storage battery, the prior art battery condition monitor cannot measure the remaining capacity of the storage battery accurately.